The present invention relates to a clip that can be attached to workpieces with different thicknesses, without play. More particularly, the invention is concerned with a clip of the type comprising a base, a shank extending from the base, and a pair of flexible legs extending from an end of the shank toward the base and away from a side of the shank.
A clip comprising a base, a shank extending from the base, and a pair of flexible legs extending from an end of the shank towards the base and away from the side of the shank is well known in the art. Engagement portions of the legs engage an edge of a mounting hole so as to mount the clip on a workpiece such as a panel when the shank and the legs are inserted into the mounting hole of the workpiece. An example of one of these clips is disclosed in Japanese Unexamined Utility Model Application Publication No. 1-113609 (Patent Document 1). In this clip, a slit is formed lengthwise in the pair of legs to divide them in two. The engagement portions divided in two are formed so as to engage the mounting hole in the workpiece. Because the pair of legs is divided in two to form a four leg configuration to engage the mounting hole, the mounting process can be performed reliably even when the dimensions of the mounting hole exceed tolerance or the hole is deformed.
A clip is disclosed in Japanese Unexamined Utility Model Application Publication No. 5-66314 (Patent Document 2) that comprises a base and a single leg extending integrally from the base. Here, the leg forms a special hook shape extending from the base. A leg with this special shape allows the clip to be mounted using a relatively small amount of insertion force. A shoulder is also formed between the base and leg that conforms to the edge of part of the mounting hole. Another shoulder is formed to conform to the edge of another part of the mounting hole. The hook-shaped leg works with the two shoulders in the mounting hole so that the clip does not come off the workpiece after being mounted.
Clips are disclosed in Japanese Unexamined Utility Model Application Publication 57-63119 (Patent Document 3: Corresponding to Examined Utility Model Application Publication 60-15941) and Japanese Unexamined Patent Application Publication 2000-46025 (Patent Document 4) that are mounted to a workpiece by inserting legs into a mounting hole on the workpiece. These clips have a base and legs that are divided vertically with a hinge connected to the base. The divided base and divided legs are connected to assemble the clip. A fuel cap engagement tool is disclosed in Japanese Unexamined Patent Application Publication 2001-191803 (Patent Document 5) that is used to engage a fuel cap without, for example, requiring a special engagement portion on part of a panel of a car body.
The clip in Patent Document 1 performs the mounting process reliably even when the dimensions of the mounting hole exceed tolerance or the hole is deformed, because the pair of legs is divided in two to form a four leg configuration to engage the mounting hole. However, this clip does not sufficiently adapt to workpieces of varying thickness, and does not engage thin workpieces effectively. An elastic plate-shaped portion can be formed on the base, and play-preventing fingers can be formed on the base or the shank to prevent play. However, such plate-shaped portions and play-preventing fingers require substantial mounting space on the workpiece. As a result, the clip cannot be used in tight places.
Because differences in plate thickness are absorbed by the front surface (exposed surface) of the workpiece, the mounting height of the clip of Patent Document 1, which depends on plate thickness, detracts from the appearance of the exposed surface. The clip in Patent Document 2 has a special-shaped leg that extends like a hook from the base. While this leg allows the clip to be mounted with very little insertion force, it cannot accommodate workpieces of varying thicknesses.
The clips in Patent Document 3 and Patent Document 4 have a base and legs that are divided vertically with a hinge connected to the base. The divided base and divided legs are connected to assemble the clip. These documents do not mention whether they can be mounted on workpieces of varying thicknesses without play. The clip in Patent Document 5 is used to engage a fuel cap without requiring a special engagement portion on part of a panel of a car body. However, this clip cannot be mounted on workpieces of varying thicknesses without play.